The effect of laparoscopic sleeve gastrectomy on serum levels of vitamin A, D and B12 and iron profile in patients with morbid obesity: Short term outcomes

INTRODUCTION: Laparoscopic sleeve gastrectomy (LSG) has emerged as a prominent surgical intervention for morbid obesity. In the present study, we aimed to evaluate the effect of LSG on serum levels of vitamins A, D, B12, and the iron profile in patients with morbid obesity.
METHODS: This single-center, retrospective cohort study was conducted at Department of General Surgery between February 2021 and March 2023. Inclusion criteria were established in accordance with the American Society for Metabolic and Bariatric Surgery (ASMBS) guidelines. Exclusion criteria were as follows: pregnant or lactating women; those receiving medications known to affect vitamin or iron levels (e.g., anticonvulsants, long-term proton pump inhibitors); having prior gastrointestinal surgeries affecting nutrient absorption. A total of 116 patients who met the inclusion criteria were enrolled.
RESULTS: The mean age of the participants was 38.7±7.5 years, and 80 of them (68.9%) were females and 36 of them (31.03%) were males. The mean preoperative BMI was 42.1±4.1 kg/m2 A comparison of parameters before and after surgery showed that serum changes in vitamins A, B12, ferritin, and TIBC were not significantly different from before surgery, indicating that long-term LSG did not alter serum levels of these micronutrients. However, serum vitamin D showed a significant difference before and after surgery (p<0.001).
DISCUSSION AND CONCLUSION: Nutritional deficiencies are a significant concern both before and after bariatric surgery. The results of the present study showed that laparoscopic sleeve gastrectomy is one of the most effective surgical methods that does not cause a lack of nutrients and vitamins in the long term.